Vivofit 2 calorie count?

I just got the Garmin Vivofit 2 yesterday and so far I really like it. The only question I have is regarding the activities calories. Today, I did 45 minutes on the elliptical with a the resistance setting on 7-8 through the majority and my activity on the Garmin Connect app showed 186 calories, walking, moderate pace. I figured out how to change the activity, but the calories didn't change. How can I make sure tomorrow's workout is recording the real activity I'm doing and not walking?